One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,5,4)(3,7,8,6)(9,10)(11,18)(12,15)(13,16)(14,17)(19,24)(20,22)(21,23)(25,26,30,29)(27,33,35,31)(28,36,37,32)(34,38,40,39)(1,3,5,8)(2,6,4,7)(12,20)(15,22)(19,23)(21,24)(25,27,30,35)(26,31,29,33)(28,34,37,40)(32,38,36,39)(9,11,14,16)(10,13,17,18)(12,19,20,23)(15,21,22,24)(25,27)(26,31)(28,34)(29,33)(30,35)(32,38)(36,39)(37,40)(1,2,5,4)(3,6,8,7)(9,12)(10,15)(11,19)(13,21)(14,20)(16,23)(17,22)(18,24)(25,28,30,37)(26,32,29,36)(27,34,35,40)(31,38,33,39)(1,4,5,2)(3,7,8,6)(9,10)(11,13)(12,15)(14,17)(16,18)(19,21)(20,22)(23,24)(9,13)(10,16)(11,17)(12,21)(14,18)(15,23)(19,22)(20,24)(25,29,30,26)(27,33,35,31)(28,36,37,32)(34,39,40,38)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.